Monthly herceptin

[Rich66]

Anyone had Herceptin once a month?
I saw this from a 2008 abstract

Trastuzumab pharmacokinetics are characterized by a low systemic clearance, a low volume of distribution (4l) and a very long half-life (28 days)

[anna4969]

Hi Rich,

Interesting. I do know that the principal investigator of the clinical trial I was doing at a major cancer center told me that herceptin stays in the body 28 days. Not the normal 21 days we always hear about so...it would be interesting to add that kind of study to the mix, but not at anyone's expense I hope. I know we still have the Hera trial out there determining 1 or 2 years, but this would be interesting as well. Speaking of the Hera trial, have you seen any results on the 2 years better than 1 one year data?

[Rich66]

Anna,
What year did the investigator tell you Herceptin is in the body 28 days? I'm wondering what made the typical dose 3 weeks or 1 week. Maybe because other infusional chemos are 3 weeks?
I am not well versed in adjuvant Herceptin results. Kind of live in the land of mets.

[Ellie F]

Rich
I asked my onc exactly the same question. He very honestly answered that the 'theory' is that herceptin may drop off cancer cells at about 3 weeks so to regive at this time appeared sensible as it may then boost back the number of bc cells covered. He stressed that this is a best guess! As herceptin is still detectable at a month they don't feel the need to give a loading dose until after this period of time has lapsed.
Elllie

[anna4969]

Rich and Ellie...

Rich, I was given that information December 2010. Thank you for inquiring not sure, as well, about the 3 week dosing but Ellie shed some light on that.

Ellie, thank you for your valuable information. That would make sense, with the loading dose not needed until a month has elapsed. I know when I continued my Herceptin past the standard one year, we just made the 28 day cut off to continue without requiring another loading dose. I, also, heard somewhere that Herceptin actually remains in the body up to 6 months after the last dose. Might you have heard the same thing? Or maybe, what was being referred to was that the effectiveness of it remains that long?

Keep the Faith